Dust-collector



2 Sheets-sheet 1 (No Model.)y

"W; A. COCKRELL.

DUST COLLECTOR No. 468,964. Patented Feb. 16, 1892.

WILL/AM COC/(HELL,

(No Model.) 2 Sheets-S'het 2 W. A. COCKRELL. DUST GOLLEGTOR Patented Feb. 16, 1892,

ma' I W/LL/VAM COCKRELL,

QMM

UNITED fSTrrrns- PATENT. OFFICE.

WILLIAM A. COCKRELL, OF MILIVAUKEE,n IVISCONSIN.

ousT-coLLElc-ro R.

SPECIFICATION forming part of Letters Patent No. 468,964, dated February 1, 1892.

Application filed October 23, 1891. Serial No. 409,575. (No model.)

.To @ZZ whom it may concern:

Beit known that I, WILLIAM A. COCKRELL, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of- Visconsin, have invented certain new and useful Improvements in Dust-Collectors, of which the following is a specificainto which chamber the dust-laden current is introduced fangentially, the drum being arranged to rotate in the direction of travel of the air-current for the purpose of maintaining the velocity thereof, and for other purposes hereinafter more fully set forth. In other particulars, which will be fully explained, the machine vdiffers materially from that set forth in the patent.

In the annexed drawings, Figure l is a transverse vertical section through my improved machine; Fig. 2, a vertical section in line with the axis of the drum, the term transverse beingr used above upon the assumption that the machine Will be of greatest length in the direction of the axis of the drum, thoughl this is not essential, and may not be the case under some circumstances.

In the drawings, A represents a separatingchamber, the walls of which are of spiral or scroll form, as shown in Fig. l, the axisof said scroll or spiral being horizontal. These walls may advantageously be made of sheet metal supported by suitable framing, andthe ends may be formed of wood,sheet metal, orv

other suitable material, as convenience and cost of construction shall determine.

At a suitable point in the circumference of the shell or casing of the chamber A there is provided a tangential inlet-spout l5, preferably opening at the top of the machine, and at a point slightlyin advance of the vertical plane of the axis of a drum or cylinder C, which is mounted within the chamber A. The width of this spout maybe greater or less, or

boards or defiectors D may be provided for varying the width and shape of the inlet-opening, though in practice these are not deemed To prevent the-passage of air between thel heads o of the drum and the end Walls of the' chamberA, a suitable packing j', of felt, wool,

or other suitable material, is provided, as shown in Fig. 2.

rlhe blades, buckets, or slats b are advisably made of the form indicated in Fig. 1-that is to say, they present in cross-section a short radial face and a longer oblique face joining 'the radial portion at an angle of from thirty to forty degrees, more or less, to the former. In practice I find it advantageous to adoptan angle of thirty-five degrees to the radius of the cylinder, for reasons that will be presently explained. These-blades are preferably made of Russia iron, and the object of bending them to the form indicated or of providing the short radial portion is to give stiffness to the blades and make them selfsupporting without unduly increasing the weight of the machine by adding spiders or other supports. I desire it to be understood, however, that I do not restrict myself to Russia iron, nor in fact to any metal or material whatever for the construction of the blades, slats, or fiights, as they may be made of any suitable material, wood answering a very good purpose.

The shaft E is placed ecccntrically within the shell or casing A, so that the space between its circumference and the wall 'of the shell or casing A decreases gradually and constantly from the discharge end of thespout or inlet B to the conveyor-trough F which is 'located below the ascending side of the drum.

'lhe purpose of thus arranging the drum and IOO shaft eccentrically with reference to the shell or casing is to compensate for the loss of air by reason of its escape betweep the blades or flights of the drum or cylinder C and from the machine, the result of this arrangement being a practically uniform air pressure through something more than one-half the circumference of the shell or casing.

' Within the shell or casing A, at-the front side or between the shell and the ascending side of the drum, at which point the casing is enlarged, there is placed a slatted rack G, consisting of cu'rved boards g and horizontal slats h, arranged in a series curving to correspond to the curvature of the drum, as plainly shown in Fig. 1. Below therack G is located the trough F', into which material is directed by a gather-board 11 and the sloping wall of the shell or casing A. The conveyor ll, working in said trough, serves to carry olf to a snitable outlet any material which may be deposited in the trough. As shown in Fig. 2, the boards g are shorter than the drum or cylinder, and there is consequently a space left at either end of said boards between them and the end Walls of the casing, through which heavy particles may pass.

Motion is imparted to the conveyor by means of a sprocket-chain passing about sprocketwheels j and k, respectively, secured upon the shaft E and the conveyor-shaft, or by means of any convenient driving-band, gear, or the like, the method of driving being unimportant.

The machine being constructed as above set "forth, its operation is as follows: Dustladen air is blown in at the top of the machine through spout B over the vtop of the cylinder C and against the concave surface of the shell, whereby it is given avortical or whirling movement within said chamber and about the cylinder. The cylinder being -put in vmotion and given a circumferential speed approximately the same as that 'of the moving air-current causes the movement of the current to continue practically the same, the

air `escaping between the blades, flights, or slats b to the interior of the drum, and finally through thecentral spiders c and the openings e of the end walls of the casing to the atmosphere or to suitable lines orducts which may be connected therewith, if deemed desirable. 1n practice, however, itis preferred to permit the escaping air to pass directly into the atmosphere.

The narrowing of the space between the cylinder C and the wall of the shell or casing A,as above explained, compensates in greater orless degree for the escape of air through the drum and causes the pressure to be practically or nearly uniform throughout said space; but upon arriving at the pointwhere the gather-boardz'meets the casing the air venters an expansion chamber or space produced by the enlargement of the casing and permits the lighter portions floating therein to fall or settle into the space behindandbelow the slats h. The heavier particles carried by the air-current and falling around the outside of the drum or cylinder pass, mainly, toward the end walls of the chamber or casing A, and through thespacebetween the ends of the slats or boards h and the end walls of the casing, and are finally delivered into the conveyor trough F'. The lighter floating-dust, which is the portion that the machine is primarily designed to collect, is found in practice to adhere to Hat smooth surfaces, and it is by reason of this adhesion that I am enabled to effectively collect the same. As the air by reason of the pressure within the shell or casing passes inward between the blades, iiights, or slats b of the cylinder C, it comes into contact with the faces of said slats; but owing tothe inclination of said slats the air is slightly thrown ed from the front faces and consequently hugs against and 4travels in contact with the rear faces of the slats, the term rear faces being used with reference to the direction of travel of the cylinder.

In practice it is found that the fine dust, which is very adhesive, deposits itself upon the rear faces of the bl-ades, slats` or fiights on the descending side of thedrum, the deposit being comparatively small at the outer the next slat. The material thus deposited upon the blades adheres thereto and is carried by them to a point on the ascending side of the drum beyond the vertical plane of the uppery edge of gather-board z'.

yGravity assists in holding the material to or upon the rear faces on the descending side of the drum and for a certain distance upward ou the ascending side; but about the time that the blades pass a radial plane extending from the axis of shaft E tothe upper edge oft-he gather-board e', gravity begins to act in the opposite Way or to cause the descent of the material, and it is discharged from the backs of the blades, the outward movement of the'air effected by the inclination of'the blades causing thematerial to be thrown toward the slatted rack G and over the conveyor-trough F-, into which it settles, the light particles being precipitated in agglomerated masses and unaffected to any considerable extent by the air-current. Thus it will be seen that on the descending side gravity, adhesion, and to a considerable extent the vertical movement of the air-cnrren t, combine to eiect a deposit of the finer material, dust, dac., upon the rear faces of the blades, while on the ascending side of the drum centrifugal action and gravity combine to free and discharge the material, which is at that point freed from air-pressure or subjected only to light pressure.

' The inclination of the blades is amatteroi great importance, and' while, as above indi- IOC) IIO

'it advisable to keep Within an inclination of from thirty to forty degrees, although I do not restrict myself arbitrarily to these limits. Measurably good results may be attained within considerably wider limits; but practical experience has demonstrated, at least to my satisfaction, that an angle of thirty-tive de: grees to the radial is conducive to the best results` It will, of course, be understood that the frame-work may be of any usual or suitable description; that materials may vary; that the particular mode of driving the cylinder is unimportant, and that the proportions of the parts may also be changed, as circumstances and the nature of the material to be operated upon may require, the proportions and relative arrangement indicated in the drawings being suchas are deemed best for the collection of ilour dust. So, too, the annular heads a of the cylinder C may be connected by stay rods or braces or simply car- 'to produce a strong outward pressure of the air and to prevent its passage inward to the escape-openings is largely neutralized and the air is enabled to travel to the outlets without undue back-pressure.

It is particularly to be noted that in the present machine the blades are thin and flat,

' their front and rear faces being parallel with each other. Some deviation from true parallelism may be permissible; but it. is important to avoid any considerable deviation, the

angle of each blade and of each face of the blade contributing materially to the attainment of theresult in view and any great departure therefrom interfering with such result.

Having thus described my invention, what I claim is- 1. In a dust-collector., the combination of a shell or casing provided with an inlet for dustladen air and a rotatable drum or cylinder mounted within said casing and having its exterior directly exposed to the incoming air, said drum consisting, essentially, of blades or flights having their front and rear faces inclined at an angle of approximately thirty to forty degrees from lines radiating from the axis of the drum or cylinder.

2. In a dust-collector,` the combination of a' shell or casing provided with an inlet at one side and a rotatable drum or cylinder located within and eccentrically to said shell or casing, said drum consisting, essentially, of aseries of slats, blades, or iiights inclined at an angle of approximately thirty to forty degrees from lines radial to the axis of the drum.

3.' The herein-described dust-collector, consisting of shell or casing A, provided with openings e in its ends, rotatable drum or cylinder C, consisting, essentially, of overlapping inclined blades b, slatted rack G, trough F, and conveyer Il.

,4. In combination with shell or casing A, provided with inlet B, drum or cylinder C, mounted eccentrically Within the casingand consisting, essentially, of overlapping slats or flights b, inclined at an angle of approximately thirty to forty degrees from lines radial to the axis ot the cylinder.

5. In combination with ashell Aor casing A, provided With inlet B, drum or cylinder C, mounted eccentrically within the casing and provided with slats or iiights b, inclined approximately at an angle of from thirty to forty degrees to lines radial to the axis of the cylinder. y

6. In combination with shell or casing A,

lprovided with an air-inlet, drum or cylinder C and slatted rack G, the slats ot' which are of a length less than that of the chamber A.

7. In adust-collector, the combination of a shell or casing provided with an inlet, and a rotatable drum located Within said shell or casing and consisting, essentially, of overlapping blades arranged oblique ,to lines projected radially from the axis of the cylinder.

8. In combination with a shell or casing, a

rotatable drum or cylinder C, mounted therein and provided With sheet-m etal blades bent or vcreased longitudinally, substantially as and lod IIC 

